As the second day of the Olympic track and field trials in Eugene, Oregon, loped to a waterlogged conclusion Saturday, two highly anticipated women's events wrapped their qualifying rounds.

Dawn Harper won in the 100m hurdles, with the perennially popular Lolo Jones squeaking her way to London having taken third. In the women's 100m dash, Carmelita Jeter handily dominated the field.

The victories these – and so many other – women enjoyed this weekend can be traced in a direct line back to the passage of Title IX.

The 1972 law that is celebrating its 40th birthday this weekend mandated that "no person in the United States shall, on the basis of sex, be excluded from participation in, be denied the benefits of, or be subjected to discrimination under any education program or activity receiving federal financial assistance".

Those 37 words had an incalculable impact on the lives of millions of girls and women. In the year that Title IX was passed, only one in every 27 high school girls participated in an organized sport. That number now stands at one in four.

"It's easy to take for granted," Amanda Smock, a professional triple jumper who secured a spot on the Olympic team Saturday, told the Guardian.

"When I was growing up I could jump at every opportunity that I came across. As I learned that the women that came before me didn't have the same ability, I thought: 'What the heck was that all about?' How incredibly grateful I am for those who started to pave the way in women's sports."

One of those women is Ellen Schmidt-Devlin, a former University of Oregon runner who competed in the 1980 trials in the 1500m race on this very track in Eugene.

Schmidt-Devlin, who was mentored by the legendary track coach and Nike co-founder Bill Bowerman, is the producer of a new documentary that takes a dramatic look at the history of her alma mater's women's track and field teams of 1985 and 2011.

We Grew Wings is a small film that focuses on the women's early track program at the University of Oregon, a school and region that has become synonymous with the sport. She is quick to credit Title IX with the successes she enjoyed at the school, and subsequently in life.

"We were the first wave," she said of her trail-blazing classmates.

But looking back, she said she was surprised to learn that the current crop of young female athletes were unaware of the debt they owed to the landmark legislation.

"Men have learned to turn around and help the next generation," she said. "We thought we made this big difference. But we turned back around and the women today don't know their history. And they have a lot of the same problems. That surprised us."

The documentary she produced, made by the Portland filmmakers Erich Lyttle and Sarah Henderson, focuses on two teams that took home national titles against great odds. In 1985, the Oregon women won the NCAA title in outdoor track. In 2011, the team took the NCAA indoor title.

Devlin-Schmidt, the mother of two grown daughters and a son, spent 27 years as a Nike executive after leaving her sport. But it was thanks to track – and thanks to Title IX – that she enjoyed success after school, she said.

"Leaders of teams, they learn leadership, they know teamwork, they know how to speak publicly," she said. "They're gaining all this confidence and they take that to the business world, to non-profits – or even raising families."